South Africa spinner Robin Peterson believes he has a major World Cup role to play as his side eye a place in the semi-finals.

"Coming to the West Indies I thought the wickets were always going to be slow and I expect, at some stage, to have a role in the tournament and I must make sure that I am ready," said Peterson.

South Africa, who take on surprise qualifiers Ireland in their second Super Eights match here on Tuesday, had to abandon their practice on Sunday after more rain left the field at the Bourda Test ground soaking wet.

Peterson said the hot and humid weather can increase his chances of featuring as support to the pace attack led by Shaun Pollock and Makhaya Ntini.

"I think because of the heat the role of a spinner was always there. You can't bowl seamers all the time and it's also important to control the over rate, change the pace of the game, so there's always a role for a spinner," said the slow left-armer who has 16 wickets from his 34 one-day internationals.

"You look to spinner to slow the run rate, just get the batsmen thinking of a certain style of bowling and as a spinner you think all the time and, if you pick up wickets, it's a bonus."

Peterson hit the winning boundary in the tense one-wicket win against Sri Lanka here last week to give his team two crucial points, which he felt were vital.

Needing just four runs to win the game with five wickets and plenty of overs to spare, South Africa were rocked by Sri Lanka paceman Lasith Malinga who became the first bowler in one-day cricket history to take four wickets off successive deliveries.

But Peterson, who failed to take a wicket in five overs against Sri Lanka, played down his great escape act as a batsman.

"I'm not a hero, I was just lucky. Obviously I'm happy that it was important to win the game and the two points came our way. The important thing was that we came out on top at the end.

"We were quite happy to get two points and the team is relaxed and looking forward to the next games. But we are not taking Ireland lightly because they gave us a scare in the warm-up match," said the 27-year-old Peterson.

He was referring to the pre-World Cup friendly in Trinidad last month when the Irish had South Africa reeling at 91-8 before Graeme Smith's side escaped with their reputation intact.